Coastline Habitat Restoration

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Great Lakes Urban Habitat Restoration Symposium
January 22 – 23, 2009
Chicago, Illinois
ABSTRACT
Author: WILLIAM J. WEAVER, P.E., D.WRE – Vice President – Sr. Principal Engineer -- AECOM, Vernon Hills, IL
Abstract Title: Great Lakes Coastline Habitat Restoration - Design Constraints and Opportunities
Great Lakes coastal habitat is a crucial part of an ecosystem within a basin that contains nearly 20
percent of the earth’s fresh water. This basin supports more than ten percent of the U.S. population, and
more than one fourth of the Canadian population. The glacial history and sheer size and characteristics
of the Great Lakes provide a diverse ecosystem. Urban development in the basin has significantly
influenced the health and diversity of this ecosystem, especially in the highly developed urban centers
where population is concentrated near the lakes. This paper explores coastline habitat restoration design
constraints and opportunities that should be considered when implementing coastal project works.
A healthy lake ecosystem is comprised of diverse physical characteristics including rocky water edges
and reefs, marshes, beaches and dunes, clean water, and shoals. Adjacent upland areas are of equal
importance in terms of their ability to buffer and complement the functional value of the coastal
environment. In urban areas, we must also consider the reality, necessity, and importance of human
activities within the coastal environment. Urban development stress as well as natural stressors such as
open coast wave climate and lake level dynamics are key reasons that can limit coastal habitat and
biodiversity. While the interaction of man and nature has not always been productive with respect to the
health of the coastal ecosystem, there are many examples where a reasonable balance exists. With
proper planning, there is much that can be done to improve the coastal ecosystem in the future.
There are numerous examples of past development activities along Great Lakes coastlines that have
caused stress and destruction of habitat. There are also areas where development has been constrained
near urban centers that contain tremendous habitat and biodiversity such as the Indiana Dunes National
Lakeshore. Furthermore, there are also many case histories of urban lakefront development that have
included habitat restoration and added significantly to the health of the ecosystem. This paper explores a
number of Great Lake shoreline areas including those where development should be carefully restricted,
and areas where proper development can be accomplished in a way that enhances the coastal
ecosystem. This presentation focuses on several case histories that illustrate habitat conditions and
restoration strategies for a variety of Great Lakes coastal environments:
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The Chicago Park District, City of Chicago and the U.S. Army Corps of Engineers have
completed more than $300 million (9 miles) of shoreline improvements in the City of Chicago
during the last decade.
Lake Michigan glacial bluff and shoreline restoration in Northern Illinois.
Illinois man-made beaches.
Presque Isle rock bluff and shoreline restoration along Lake Superior.
Lake Michigan glacial bluffs and shoreline in central Michigan.
“Accidental” habitat.
As the push for sustainable design has taken hold during the last decade, shoreline habitat has received
more attention. Sustainable design concepts are gradually seeping into the lexicon and regulations of
agencies that are responsible for coastal development. While funding for coastal habitat restoration
remains difficult to come by, there is much that can be accomplished by influencing the design of public
and private coastal projects. Coastal habitat enhancement can often be incorporated into these designs
for little or no added cost. There is still much work that needs to be done to better understand the Great
Lakes coastal ecosystem so that urban planners can effectively influence coastal project works.
However, there is still much that can be accomplished by simply considering the following basic design
tenets: reduce lakefront erosion – especially in areas containing nutrient rich soil; consider treatments that
can enhance water quality; create diverse coastal environments using clean stone, sand and plant
materials; and inclusion of habitat enhancement as a key goal in the planning process.
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